报错内容：Something went wrong while saving this configuration: Area is already set

修改
vendor/magento/module-email/Model/AbstractTemplate.php

public function setForcedArea($templateId)
{
if ($this->area) {
throw new \LogicException(__('Area is already set'));
}
$this->area = $this->emailConfig->getTemplateArea($templateId);
return $this;

}
to